001    /*
002     $Id: VariableExpression.java 3419 2006-01-19 00:07:02Z blackdrag $
003    
004     Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005    
006     Redistribution and use of this software and associated documentation
007     ("Software"), with or without modification, are permitted provided
008     that the following conditions are met:
009    
010     1. Redistributions of source code must retain copyright
011        statements and notices.  Redistributions must also contain a
012        copy of this document.
013    
014     2. Redistributions in binary form must reproduce the
015        above copyright notice, this list of conditions and the
016        following disclaimer in the documentation and/or other
017        materials provided with the distribution.
018    
019     3. The name "groovy" must not be used to endorse or promote
020        products derived from this Software without prior written
021        permission of The Codehaus.  For written permission,
022        please contact info@codehaus.org.
023    
024     4. Products derived from this Software may not be called "groovy"
025        nor may "groovy" appear in their names without prior written
026        permission of The Codehaus. "groovy" is a registered
027        trademark of The Codehaus.
028    
029     5. Due credit should be given to The Codehaus -
030        http://groovy.codehaus.org/
031    
032     THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033     ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034     NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035     FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
036     THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037     INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039     SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041     STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043     OF THE POSSIBILITY OF SUCH DAMAGE.
044    
045     */
046    package org.codehaus.groovy.ast.expr;
047    
048    import org.codehaus.groovy.ast.ClassHelper;
049    import org.codehaus.groovy.ast.ClassNode;
050    import org.codehaus.groovy.ast.GroovyCodeVisitor;
051    import org.codehaus.groovy.ast.Variable;
052    
053    /**
054     * Represents a local variable name, the simplest form of expression. e.g. "foo".
055     * 
056     * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
057     * @version $Revision: 3419 $
058     */
059    public class VariableExpression extends Expression implements Variable {
060    
061        public static final VariableExpression THIS_EXPRESSION = new VariableExpression("this", ClassHelper.DYNAMIC_TYPE);
062        public static final VariableExpression SUPER_EXPRESSION = new VariableExpression("super", ClassHelper.DYNAMIC_TYPE);
063    
064        private String variable;
065        private boolean inStaticContext;
066        private boolean isDynamicTyped=false;
067        private Variable accessedVariable;
068        boolean closureShare=false;
069    
070        public Variable getAccessedVariable() {
071            return accessedVariable;
072        }
073    
074        public void setAccessedVariable(Variable origin) {
075            this.accessedVariable = origin;
076        }
077    
078        public VariableExpression(String variable, ClassNode type) {
079            this.variable = variable;
080            super.setType(ClassHelper.getWrapper(type));
081        }
082        
083        public VariableExpression(String variable) {
084            this(variable, ClassHelper.DYNAMIC_TYPE);
085        }
086        
087        public VariableExpression(Variable variable) {
088            this(variable.getName(), variable.getType());
089            setAccessedVariable(variable);
090        }
091    
092        public void visit(GroovyCodeVisitor visitor) {
093            visitor.visitVariableExpression(this);
094        }
095    
096        public Expression transformExpression(ExpressionTransformer transformer) {
097            return this;
098        }
099    
100        public String getText() {
101            return variable;
102        }
103        
104        public String getName() {
105            return variable;
106        }
107    
108        /**
109         * @return true if this variable is dynamically typed
110         */
111        public String toString() {
112            return super.toString() + "[variable: " + variable + (this.isDynamicTyped() ? "" : " type: " + getType()) + "]";
113        }
114    
115        public Expression getInitialExpression() {
116            return null;
117        }
118    
119        public boolean hasInitialExpression() {
120            return false;
121        }
122        
123        public boolean isInStaticContext() {
124            if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isInStaticContext();
125            return inStaticContext;
126        }
127        
128        public void setInStaticContext(boolean inStaticContext) {
129            this.inStaticContext = inStaticContext;
130        }
131    
132        public void setType(ClassNode cn){
133            super.setType(cn);
134            isDynamicTyped |= ClassHelper.DYNAMIC_TYPE==cn;
135        }
136        
137        public boolean isDynamicTyped() {
138            return isDynamicTyped;
139        }
140    
141        public boolean isClosureSharedVariable() {
142            if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isClosureSharedVariable();
143            return closureShare;
144        }
145        
146        public void setClosureSharedVariable(boolean inClosure) {
147            closureShare = inClosure;        
148        }
149        
150        public ClassNode getType() {
151            if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.getType();
152            return super.getType();
153        }
154    }